• 

ivermectin and moxidectin are the only macrocydic lactones available for use in horses. ivermectin is used in horses at a dosage of 200 mg/kg, where as moxidectin is used a 400 mg/kg. Both ivermectin and moxidectin are effective against a broad range of adult and migrating larval stages of nematode (including large and small strongyles) and arthropod (Gasterophilus spp) parasites.